In recent years a technology known as “plenoptics” has started to become realizable. In plenoptics, a special set of optical elements is employed to collect and record image data (of an object) that can be processed to emulate three-dimensional images, from various angles, of the object. The typical set of optical elements for recording plenoptic images includes, a main lens, which can effectively be a simple round lens, a lenticular grating, and a recording device, having pixel sized photosensitive photosensors arranged so that multiple pixel areas correspond to different locations within each lenticule. Image data from particular subsets of photosensors is selected, and the image data from the subsets is suitably processed; in this way, images corresponding different to viewing angles relative to an object can be obtained, substantially without ever moving the elements relative to the object. Some documents describing the rudiments of plenoptic image recording include U.S. Pat. Nos. 5,076,687 and 7,038,184.
A challenge in the art of office equipment is the accurate digital recording (such as for copying or scanning) of original images from bound books or other odd-shaped originals, such as packages. Ideally, an image-bearing sheet should be in full contact with a platen, so that all portions of the sheet can be predictably focused upon. With an open, bound book, however, very often the portion of any page near the binding will not be in contact with the platen, and will thus be out of focus with regard to the optical elements in the copier or scanner, resulting in a distorted, improperly illuminated, and unfocused portion of the image. Many approaches have been tried to overcome this difficulty, including applying special calculations to the recorded digital data (which may require multiple scans of the original image), as shown in U.S. Pat. Nos. 6,763,141 and 7,170,644.
A challenge in the art of printing equipment is the accurate digital recording (such as for copying or scanning) of original images on sheets moving at high speed through a baffle. At high speeds the sheet is often not urged against one side of the baffle, such as a side having a window therein. Thus, a photosensor array recording images on the sheets may not be able to focus on a predictable zone within the baffle.
U.S. Pat. Nos. 5,521,695 and 6,969,003, and the article by Ng and Hanrahan, “Digital Correction of Lens Aberrations in Light Field Photography,” Optical Design Conference 2006, SPIE Vol. 6342, each describe techniques, using approaches similar to those used in plenoptics, to improve the depth of field and other optical qualities of lens systems.